Animals such as mammals and birds are often susceptible to parasite infestations/infections. These parasites may be ectoparasites, such as insects, and endoparasites such as filariae and other worms. Domesticated animals, such as cats and dogs, are often infested with one or more of the following ectoparasites:                fleas (e.g. Ctenocephalides spp., such as Ctenocephalides felis and the like);        ticks (e.g. Rhipicephalus spp., Ixodes spp., Dermacentor spp., Amblyomma spp., and the like);        mites (e.g. Demodex spp., Sarcoptes spp., Otodectes spp., and the like);        lice (e.g. Trichodectes spp., Cheyletiella spp., Linognathus spp. and the like);        mosquitoes (Aedes spp., Culex spp., Anopheles spp. and the like); and        flies (Haematobia spp., Musca spp., Stomoxys spp., Dermatobia spp., Cochliomyia spp. and the like).        
Fleas are a particular problem because not only do they adversely affect the health of the animal or human, but they also cause a great deal of psychological stress. Moreover, fleas are also vectors of pathogenic agents in animals and humans, such as dog tapeworm (Dipylidium caninum).
Similarly, ticks are also harmful to the physical and psychological health of the animal or human. However, the most serious problem associated with ticks is that they are the vector of pathogenic agents in both humans and animals. Major diseases which are caused by ticks include borreliosis (Lyme disease caused by Borrelia burgdorferi), babesiosis (or piroplasmosis caused by Babesia spp.) and rickettsioses (also known as Rocky Mountain spotted fever). Ticks also release toxins which cause inflammation or paralysis in the host. Occasionally, these toxins are fatal to the host.
Likewise, farm animals are also susceptible to parasite infestations. For example, cattle are affected by a large number of parasites. A parasite which is very prevalent among farm animals is the tick genus Rhipicephalus (Boophilus), especially those of the species microplus (cattle tick), decoloratus and annulatus. Ticks, such as Rhipicephalus (Boophilus) microplus, are particularly difficult to control because they live in the pasture where farm animals graze.
Animals and humans also suffer from endoparasitic infections including, for example, helminthiasis which is most frequently caused by a group of parasitic worms categorized as cestodes (tapeworm), nematodes (roundworm) and trematodes (flatworm or flukes). These parasites adversely affect the nutrition of the animal and cause severe economic losses in pigs, sheep, horses, and cattle as well as affecting domestic animals and poultry. Other parasites which occur in the gastrointestinal tract of animals and humans include Ancylostoma, Necator, Ascaris, Strongyloides, Trichinella, Capillaria, Toxocara, Toxascaris, Trichuris, Enterobius and parasites which are found in the blood or other tissues and organs such as filarial worms and the extra intestinal stages of Strongyloides, Toxocara and Trichinella. 
Recently, isoxazole and isoxazoline-containing compounds have been demonstrated to be effective against parasites that harm animals. For example, U.S. Pat. No. 7,964,204 and U.S. Pat. No. 8,410,153 (to DuPont, both incorporated herein by reference) disclose isoxazoline compounds according to Formula (I) below, which are active against ectoparasites and.

A particularly active isoxazoline compound, 4-[5-[3-chloro-5-(trifluoromethyl)phenyl]-4, 5-dihydro-5-(trifluoromethyl)-3-isoxazolyl]-N-[2-oxo-2-[(2,2,2-trifluoroethyl)amino]ethyl]-1-naphthalenecarboxamide, is known by the nonproprietary name afoxolaner. Afoxolaner has the following chemical structure:

Other isoxazoline compounds that have been found to be highly active against parasitic insects and arachnids are known by the nonproprietary names fluralaner (see U.S. Pat. No. 7,662,972, which is incorporated herein by reference), sarolaner (see US 8,466,15, incorporated herein by reference) and lotilaner (see, for example U.S. Pat. No. 8,383,659, incorporated herein by reference). The structures of these compounds are shown below:

In addition, published patent application nos. US 2010/0254960 A1, WO 2007/070606 A2, WO 2007/123855 A2, WO 2010/003923 A1, U.S. Pat. No. 7,951,828 & U.S. Pat. No. 7,662,972, US 2010/0137372 A1, US 2010/0179194 A2, US 2011/0086886 A2, US 2011/0059988 A1, US 2010/0179195 A1 and WO 2007/075459 A2 and U.S. Pat. No. 7,951,828 (all incorporated herein by reference) describe various other parasiticidal isoxazoline compounds.
It is known in the field that isoxazoline compounds having a chiral quaternary carbon atom such as the carbon atom adjacent to the oxygen on the isoxazoline ring of the compounds described above have at least two optical isomer (enantiomers) that are mirror images of each other. Furthermore, it is sometimes the case with biologically active compounds that one of the enantiomers is more active than the other enantiomer. In addition, it is sometimes the case that one enantiomer of a biologically active compound is less toxic than the other enantiomer. Therefore, with optically active compounds it is desirable to utilize the enantiomer that is most active and less toxic (eutomer). However, isolating the most active enantiomer from a mixture can be costly and result in waste of up to half of the racemic mixture prepared.
Processes to prepare certain isoxazoline compounds enriched in an enantiomer using some cinchona alkaloid-derived phase transfer catalysts have been described. For example, US 2014/0206633 A1, US 2014/0350261 A1, WO 2013/116236 A1 and WO 2014/081800 A1 (incorporated herein by reference) describe the synthesis of certain isoxazoline active agents enriched in an enantiomer using cinchona alkaloid-based chiral phase transfer catalysts. Further, Matoba et al., Angew. Chem. 2010, 122, 5898-5902 describes the chiral synthesis of certain pesticidal isoxazoline active agents. However, these documents do not describe the processes and certain catalysts described herein.